Work-shifting mechanism sob sewing- machines



A. H. DE VOI-.

.WORK SHIFTING MECHANISM FOR SEWING MACHINES APPLICATIQN FILED FEB. 2l,19|?. l

Patented May 16, 1929.

2 SHEETSSIIEET I.

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INVENTOR MMM TI'ORNEY A. H. DE VOE. WORK SHIFTING MECHANISM FOR SEWINGMACHINES.

APPLICATION FILED FEB. 2l. |917.

Patented May 16, 1922.

2 SHEETS-SIIEET 2.

ATTORNEY Cil UNITED srAflgs Partnr ortica.

ALBERT n.

DE VQE, 0F WEST'FIELD, NEW JERSEY, ASSIGNOR TO THE SING-ER MANU-FACTURING COMPANY, A CORPRATON OE NEW JERSEY.

Laiaoos.

Specification of Letters Patent.

`Pa.tent-edMay 16, 1922.

Application filed February 21, 1917. Serial No. 150,003.

T0 all fwiomc' may concern.'

Be it known that 1ALennr H. Dn Voir, a citizenof the United States,residing at lVestfield, in the county ofUnion and State of New Jersey,have invented certain `new and useful improvements in TWork-ShiftingMechanisms for Sewing Machines, of which the folio 'ing is aspecification, reference being had therein to the accompanying drawings.

This invention relates to an improvement in sewing machines forproducing spaced groups or successions ofstitches, and is directedparticularly to means for producing relative shifting movements betweenthe stitch-forming mechanism and the worlr intermediate stitchingperiods7 with means of control whereby each group or succession ofstitches relative to the preceding group may be positioned eitheruniformly within a series or arbitrarily at` the will of the operatorpreparatory to the production ofany individual group or succession ofstitches.

lVhile the present improvement is not limited to embodiment in machinesof any one of various types,`it has been designed particularly for usein connection with the buttonhole cutting and stitching machine formingthe subject of my pending applications Serial No. 69,6414-, filedDecember 31, 1915. and Serial No. 135,15@ filed December 5, 1916.

Heretofore, provision has been made in buttonhole machines fortheautomatic shift of the work between stitching positions to space thebuttonholes, with the object of saving time by automatic control of 'thestich-forming and work-handling devices throughout a plurality ofbuttonhole-produr-ing cycles; but the means to this end heretoforedevised have been found impractical in commercial operation because of alack of the necessary flexibility to adapt the machines for the varyingconditions com.- monly encountered in the manufacture of garments.

V The work-shifting means of my said application Serial No. 69,644 hasfor one of its important objects a capacity for variation,

by predetermined adjustment, in the angular relation of successivelyproduced b uttonholes, while effecting a uniform' spacing of the sameapart; while the corresponding mechanism of my said application SerialNo.

.135,154 sought to further increase the ilexibility of themechanism toaccommodate different working conditions by providing not only for therendering of the same ineffective when required,but by making itcontrollable arbitrarily to vary the normal length of shift betweenstitching positions at any stage .of a continuous series ofbuttonhole-producing cycles.

The present invention has for its object to still further increase thecapability of this class of mechanism to accommodate itself to normalworking conditions by not only increasing the range of adjustment in theangular relation of successive buttonholes of a series but by subjectingsuch adjustment to arbitrary manual control, so that the operator maydetermine precisely the position of any buttonhole both regarding itsangular relation to and its spacing from the preceding buttonhole.

ln its preferred embodiment, the improvement comprises suitablestitch-forming and work-feeding mechanisms in, conjunction with atraveling work-gripping device, which latter may consist of the opposedcutting elements of a buttonhole cutting device with means for applyingto said elements iirst a yielding work-gripping closing movement uponthe work preparatory to a workshitting movement, followed by a secondstage or cutting movement for producing the buttonhole slit atitsarrival in stitching position. `The cutting device preferably cornprisesa travelling frame or carrier sustaining both ofthe cooperating cuttingelements and having a transverse sliding connection at one point with afulcrum-stud around `which it has turning movements and relative towhich it has bodily shifting movements. This carrier has independentconnections at separated points by means of suitable pitmen 'withcrank-arms upon an actuating rock-shaft of which that controlling thebodily .transverse movement of. said `carrier relative to thefulcrum-stud is adjustable upon its respective crank-arm toward and fromthe rock-shaft for both uniform and arbitrary or manual control so as tovary or 'substantially prevent movement of the carrier transversely toits fulcrum-stud in conjunction with the turning movements imparted'bythe other of said link connections.

Further objects and constructive features of the present improvementwill be understood by reference 'to the following detailed descriptionin connection with the accompanying drawings, in which- Fig. 1 is a sideelevation of a buttonhole cutting and stitching machine embodying thepresent invention. Fig. 2 is an enlarged gti-ont elevation and Fig. 8 aplan of the work-shitting and cutting mechanism detached from the otherparts of the machine. Fig. 4 is an elevation representing the means forimparting operative movements to the actuating rock-shaft, and Fig. 5 isa rear side elevation representing the means for producing thework-gripping and cutting movements of the slit-cutting device.

As shown in the drawings, the machine is constructed with a framecomprising vthe base 1` from which rise the standards 2 sustaining incoaxial relation the main-shaft 8 and the constantly running drivingpulley 4 imparting. through suitable clutch devices and Votherconnections. operative movements to the several trains of mechanism.

Slidingly mounted upon the base 1 is the travelling stitch-'frame 5sustaining a bracket member 6 in which is ournaled the reciprocatingneedle-bar 7 carrying the needle 8 cooperating in practice withlooptaking elements sustained by the frame 5. These stitch-formingelements are suitably mounted in their respective supports to performpartial rotations in buttonhole stitching cycles by means of anoperative connection with the feed-cam 9 which derives its operativemovements from connections with the main-shaft 8.

The longitudinal feeding or stitch-spacingA movements and the lateralside-shift movements are imparted to the stitch-trame by connectionswith the feed-cam including roller-studs 10 and 11, respectively,entering suitable cam-grooves in the lower face of the feed-cam cylinder9.

The non-travelling work-holder, in which the work is held during thesuccessive stitching cycles, is not shown herein as it forms no materialpart of the present invention, but it may be constructed for cooperationwith the buttonhole cutting mechanism as represented in my said pendingapplications.

As represented in the drawings, the travelling work-gripping andcuttingy device comprises a vertically and horizontally movablecutter-lever 12 having intermediate its ends a-vertical tubular boss 13in which is fitted the guide-studv 14 depending from the laterallyextending thrust-.plate 15 which has the forked lug` 16 embracing thesteady pin 17 carried by the cutter-lever 12. The collar 18 fixed uponthe enlarged lower end of the guide-stud 14 rests uponr a fixed part ofthe `machine base 1, and between the shoulder afforded by the enlargedportion of said stud and the upper end of a socket surrounding the samewithin the boss 18 is interposed a spring 19 by means of which thecutter-lever is normally maintained yielding-ly in upper or inoperativeposition.

Secured upon the Jfree end ot the thrustplate 15 is the cutter-block orplate 2O disposed beneath and in operative relation with the relativelymovable upper cutting knife 21 sustained by the overhanging member 22 ofthe cutter-lever or frame. rlhe upper and lower cutting elements 21 and20 are maintained normally separated by the previously described actionof the spring 19.

The cutter-lever is formed at its Yforward end with a transverseapertured boss 28 in which is secured by set-screws 24 the slidepin 25mountd in alined transverse bearing apertures in the spaced members 26of a yoke 27 having its hub 28 journaled upon the fixed headedfulcrum-stud-29 which is ecured by the set-screw 30 within a verticalaperture of the bracket-member 81 sustained by the base 1. The cuttingdevice, comprising the frame or carrier 12 with the cutting elements 20and 21, is thus supported at its forward end upon the pivotally mountedyoke 27 and at a point intermediate its ends by means of the guide-stud14 resting upon the base 1.

As set forth in my said applications, the cutter-lever has at its innerend adjacent the overhanging member 22 a boss 32 in which is secured astud 83 carrying a roller 34 adapted for engagement with the loweroperative face of thc rail 35 sustained at the lower end of theslide-frame 86. The slide-frame 36 is formed with apertured upper andlower lugs 37 and 318 fitted uponthe vertical push-rod 39 which isjournaled in suitable bearing members 40 vand 41 of the frame extension2.

The rod 39 has fixed thereon in its lower portion the collar 42 carryingthe laterally extending roller-stud 48 and normally pressed upwardly bymeans of a spring 44 interposed between the same and the lower bearing41, the elevated position ot' the rod 39 being determiuedby engagementor' the collar l5 fixed upon its lower end with the bearing member4l.interposed between the upper lug 87 oIn the slide-frame 86 and a thrustnut 46 applied to the threaded upper portion of the push-rod 39 is aspring 47 acting to press the slide-frame Vdownwardly with its lug 38seated upon the collar 42 (Fig. 5). lower portion of the frame 36 andthe collar 42 respectively are the forked arms 48 and 49 embracing thesteady pin 50 rising` from a depending portion 2 of the frame extension2', by means of which the parts are prevented 'from turning.

The roller-stud 48 normally lies within the path of movementof thecam-block 51 secured upon the periphery of the cam-cylinder 9 andprovided with a backwardly and VExtending laterally from the4 ries withit the roller-stud 34 and cutter-` lever 12 and thus causes the uppercutting element 21 to approach the lower cutting element 20 andyieldingly grip the work between them. The force of this grippingactionis determined by the strength of the spring 47 under the normaltension placed thereon by the thrust-nut 46.

The front side face of the rail 35 is formed in the end portion farthestfrom the cutterlever with'a vertical channel laterally closed by acap-plate 35 to afford a guideway for the vertically reciprocatingplunger-bar 52 pivotally connected at its upper end with the lowerextremity of thev pitman 53 whose 0pposite end is pivotally attached tothe shorter arm of a rock-lever 54 mounted, upon the fixed fulcrum-pin55 and having its other arm provided with the lateral roller-stud 56(Fig. 1). The roller-stud 56 is normally maintained byV means of asuitable spring (not shown) resting upon the upper face of thecutter-actuating cam-disk 57 formed with the actuating projection 58 bymeans of which the rock-lever 54 is tilted for reciprocation of theplunger-bar 52. The cam-disk 57 is fixed upon the vertical shaft 59having speed-reducing worm-and-worm wheel connection with the main-shaft3, as represented in dotted lines in Fig. 1, and carries a. drivingpinion 60 meshing with a gear-wheel 61 secured tothe cam-wheel 9 andfrom which the latter derives its operative movements.

lNith its connections with the main-shaft represented in the drawings,the cutter-actuating shaft 59 performs several rotations in each`button-hole-producing cycle, and the plunger-bar 52 performs a likenumber of reciprocations, all but one of which are idle or ineffective.As the cutting device, with the work gripped between itscuttingelements, reaches stitching position in a work-shifting movement, theroller-stud 34 assumes a posiytion beneath the end of the then retractedplunger-bar which in its next descent thrusts such roller-studpositively downward and thereby depresses the cutter-lever 12 and forcesthe upper cutting element through the work to cut the buttonhole slit.At this point in the cycle of the machine, the untilthen open worl-clamp is closed upon the work, the cutting elements separated and thecutting device withdrawn laterally into retracted position and thestitching of the buttonhole is performed as usual.

Journaled in bearings 62 upon the base -1 isa rock-shaft `63provideduponits rear-` ward end (Figs. 1 and 4) with a crank-arm 64carrying a roller-stud 65 extending beneath the straight lower operativeedge 66 y roch-shaft 63.`

of a lever 67 fulcrumed at 68 upon the post 69 rising from the base 1.The lever 67 has at its Lipper edge intermediate its ends the extension70 to the face of which is secured by means of screws 71 the angulartappet member 72, the opposite end portions of whose upper edge aredownwardly inclined for successive engagement with the rollerstuds 73projecting from the periphery of the cam-cylinder 9. The engagement ofthe tappet-member 72 by the studs 73 causes first the gradual depressionof the lever 67, then the maintenance :of the same in depressed positionand the final gradual release of thesame to permitit to vreturn toinitial. elevated position, the rock-shaft 63 performing correspondingrocking movements by reason of the described connections.

The rock-shaft 63 has secured thereon the split hub 74 of an upwardlyextending arm 7 5 which is provided with the forwardly eX- tendingsleeve 7 6, Upon this sleeve and adjacent the hub 74 is loosely mountedthe hub 77 of a lever 7 8 having therein' a series of apertures 79disposed in slightly angular and'intersecting relation with acorresponding series of holes 6() inthe level' 7 5. Theseoverlying'levers are adapted to be coupled together in different angularrelations by means of the pin r81 entering registering holes at thecrossing of the two series, as represented in dotted'lines in lligj2.-The lever carries a ball-stud 82 embraced by a strap at one endv of apitman 83 whose opposite end is provided with a similar strap einbracinga ball-stud 34 carried by the cutter-lever 12 adjacent the roller-stud34 (Fig. 4

`Surrounding the rock-shaft` 63 is the spring 85 having one end fixed tothe rearward bearing 62 and the opposite endrsecured to a'collar 86fixed upon said rockshaft and acting upon the latter to yieldinglymaintain a stop-screw 87 carried by the hub 77 of the lever 7 8 incontact with a stopplate 88 vwhich is sustained by an arm of theplural-armed treadle-actuated lever 89 fulcrumed at 90 and having a.lateral arm adapted for engagement with thestop-spring 9' (Figl 1)Secured upon the forward end of the sleeve 76 is a split collar 92 atone end of a forwardly extending bar'93 formed at the other end with ahub 94 carrying a steady pin 95 entering an aperture of the machineframe. Extending upwardly from the hub` 94 is a segmental crank-arm 96formed with a curved slot 97 which is entered by a studpin 98 movablewithin said slot toward and from the: steady pin 95 upon the axis of theThe stud-pin 98 is formed at one end with a ball 99 embraced byy a strapat the end of a pitman-lever 100 formed intermediate itsV ends with asecond strap embracing a ball-stud 101 sustained by the boss 23 of thecutter-lever 12.

The pitman-lever has adjacent the stud-pin 98 an extension 102 aperturedto receive one end of a spring 103 whose opposite end is connected to astud 104 sustained by the bed 1. rIhe pitman-lever 100 has an oppositelydirected extension apertured to receive a treadle connection representedin the form of a chain 106. The crank-arm96 has adjustably securedthereon by means of the clamp-screw 107 passing through the slot 97 adivided stop-block 108 adapted to arrest the pitman-lever 100 in apredetermined initial position of adjustment under the action of thespring 103, while permitting such pitman-lever to be moved by theoperator in opposition to said springv under the action of the treadleconnection 106.

In the rocking of the shaft 63 under the action of the cam-Wheel studs73 upon the tappeti-member 72, the crank-arms 75 and 96 are moved in thedirection of the stitchforming mechanism, thereby acting through thepitmen 83 and 100 to move two spaced portions of the cutter-lever 12defined by the ball-studs 84 and 101 in the same direction but in extentcorresponding with the distances of the ball connections 82 and99 fromthe, axisof the shaft 63.

Obviously the crank-arm 75 imparts to the cutter-lever a turningmovement about the fulcrum-st-ud 29 while the crank-arm 96 is adapted toimpart to the opposite end of the cutter-lever a bodily movement uponthe slide-pin 25 transversely of such fulcrumstud. These independentmovements derived from the actuating rock-shaft are thus adapted toproduce a resultant curvilinear movement of the intermediately disposedcutting elements (Fig. 3) of which the curvature is determined by therelativeamplitudes'of the component movements.

The length of the crank-arm 96 isi so proportioned relatively to thepitman connection of the crank-arm 7 5 that when the stud 98 is in itshighest position, as represented in Fig. 2, the effective lengths ofsaid crankarms are the same, and in the actuation of the rock-shaft 63its described connections with the cutter-lever 12 act as aparallelmotion device of which the cutter-lever is a member, whereby thelatter is caused to move rectilinearly, every point in such leverperforming a. rectilinear movement of the same extent as every otherpoint. 'The release of the treadle connection and adjustment of thestop-block 108 to any position intermediate the outer end of thecrank-arm' 96 and its axis of movement permits the connection betweenthe pitman-lever 100 and said crankarm to assume such a position thatthe pivotally mounted end of the cutter-lever will perform a bodilymovement transverse to the fulcrum-pin of less extent than the oppositeend of the cutter-lever, thereby imparting to the cutting elements amovement in a substantially circular path of a degree of curvaturedetermined by said adjustment.

It is of course obvious that, the adjustment of the pitman-leverconnection, with its respective crank-arm may be adjusted within thelimits for which the machine is designed so as to determine the exactangular reletion between the initial orvfretracted position and final orstitching position of the cutting elements, and that it is not essentialthat their path of movement intermediate these positions should beprecisely circular.

In the machine represented in the drawings, provision is made fortemporary displacement of the upper and lower stitchforming elements, asalso the needle-throat v 109 and a section. 110 of the work-plate, to

enable the cutting elements to move into stitching'position in shiftingthe work, between buttonhole positions and cutting the same to form eachbuttonhole-slit preparatory to a stitching operation.

In the use of the machine as thus described, the coupling pin 81 isadjusted within the requisite registering apertures 79 and 80 todetermine the normal retracted position of the crank-arm 75, and thestop-block 108 is set to produce the requisite effective length of thecrank-arm 96 for movement of the cutting elements 20 and 21 in a path ofthe desired curvature. The machine being set in motion and the cuttingelements having been lightly pressed upon the work to gripl the same,the cam-wheel studs 73 act upon the lever 67 to effect the rocking ofthe shaft 63 by means of which the opposite ends of the cutter-carrierare movedbaclnvardly to carry the cutting elements into stitchingposition in a curved path at the end of which the cutting knife 21invariably assumes a position in parallelism with the direction of feedand in fixed relation with the stitchforming elements. The cuttingelements having performed their second or cutting stage of movement toproduce the buttonhole slit iny cutting position, the worle is clampedin the work-holder and the cutting elements separated and returned toinitial retracted position, the stitching succeeding the cuttingoperation in the usual manner.

In operation upon the buttonhole flap of a shoe upper, the buttonholesshould not maintain their parallelism throughout the series, but theirangular relation well as their spacing apart requires modification,dependingvupon theclass of worl; operated' upon. In the machineof thepresent improvenient, the angular relation of the knife 21 in itsinitiall retracted and final positions may be varied by the manualtilting of the pitman-lever 100 so as tovary its point of connectionwith the crank-arm 96, and this change may be effected in any degreebetween the normal position determined by the i, so

i is retracted from cutting position.

stop-block 108 and extreme straight-line position, as represented inFig. 2, depending entirely upon the `will of the operator. As describedin my said application Serial No. 135,154, the spacing apart of thebuttonholes .may be changed arbitrarily without disturbing the normaladjustment of the machine by the manual operation of the stop-platecarrying lever 89 so as to change the initial retracted position of thecrank-arms 7 5 and 96. Thus, the present machine provides means forchanging, both normally and arbitrarily on the part of the operator,both the initial position andthe angular relation of the cuttingelements in respect to their position at the button hole cutting point.It will be observed that the capacity of the present mechanism forvariation of its effect upon the work is due to the provision foradjustment which is constantly under the control of the operatorthroughout substantially the entire cycle of operation of the machine,or at all times at which the cutting device Under such condition,`changes in the path or direction of travel of the cutting device may bemade arbitrarily by the operator for any individual buttonhole of a`connected series of which the component buttonholes are adapted to beautomatically produced and spaced in sequence in each cycle of operationof the machine. The manual control l of the relative `location of thebuttonholes i ing largely upon the type of machine to which it may beapplied; and it is therefore evident that the invention is not limitedto the construction and arrangement of parts herein shown and described.

I-Iaving thus set forth the nature of the invention, what I claim hereinis 1. In a sewing machine, in combination, stitch-forming and feedingmechanisms for producing within a stitching cycle stitching upon thework in a defined pattern, and means acting upon the work and adapted toshift beyond the normal range of action of the stitch-forming mechanismthat portion of the work last within such range in the stitching of saidpattern, and comprising a work-gripping device, and shifting means formovlng it in a predetermined path and provided with adjusting meanswhereby said gripping device may be caused to travel eitherin arectilinear or a curvilinear path.

2. In a sewing machine, in combination,

stitch-forming and feeding mechanisms for producing within a-stitchingcycle stitchingT upon the work in a defined pattern, and work-shiftingmeans acting upon the work intermediate stitching cycles and comprisinga work-gripping device, and shifting means adapted to move the same in acurved path and provided with adjusting means whereby the degree ofcurvature of said path may be varied at will between a predeterminedmaximum degree and a straight line.

3. In a sewing machine, in combination, stitch-forming mechanism,feeding mechanism for effecting the spacing of the stitches in the work,and work-shifting means acting independently of the feeding mecha-l,nism and comprising a work-gripping device, a fulcrum, and connectedmeans for shifting said gripping device respectively about and bodilytransversely of said fulcrum.

l. In a sewing machine, in combination, stitch-forming mechanism,feeding mechanism for effecting the spacing of the stitches in the work,and work-shifting means acting independently of the feeding mechanismand comprising a work-gripping device, a fixed support, a fulcrumsustained thereby, and means for imparting to said gripping devicecompound shifting movements relatively to said fixed support about andtransversely of said fulcrum.

5. In a sewing machine, in combination, stitch-forming mechanism,feeding mechanism for effecting the spacing of the stitches in the work,and work-shifting means acting independently of the feeding mechanismand comprising a work-gripping device comprising opposed grippingelements and a carrier therefor, means connected to said carrier atspaced points forshifting the same, and means for varying the effectiveactionof the respective carrier-shifting means.

6. In a sewing machine, in combination, stitch-forming mechanism,feeding mechanism for effecting the spacing of the stitches in the work,and work-shifting means acting independently of the feeding mechanismand comprising a work-gripping device, a fixed fulcrum, and means forturning said gripping device upon and for shifting it bodilytransversely of said fulcrum.

7. In a sewing machine, in combination, stitch-forming mechanism,feeding mechanism for effecting the spacing of the stitches in the work,and work-shifting means aeting independently of the feeding mecha-` nismand comprising a work-gripping device, a fixed fulcrum, a transverseguideelement mounted upon said fulcrum with which said gripping devicehas a sliding` connection, and means for turning said gripping deviceupon and for shifting it bodily transversely of said fulcrum.

8. In a sewing machine, in combination, y stitch-forming mechanism,feeding mechanism for effecting the spacing` of the stitches in thework, and work-shifting means acting independently of the feedingmechanism and comprising a work-gripping device, a fixed fulcrum, meansfor turning said gripping device upon and for shifting it bodilytransversely ot said fulcrum, and adjusting means for relativelychanging the extent of said turning and bodily shifting movements.

9. In a sewing machine, in combination, stitch-forming mechanism,feeding mechanism for effecting the spacing of-the stitches in the work,and work-shifting means acting independently of the feeding mechanismand comprising a work-gripping device, a fixed fulcrum, means forturning said gripping device upon and for shifting it bodilytransversely of said fulcrum, and adjusting means connected with saidbodily shifting means and adapted to vary the extent of said "bodilyshifting movements.

10. In a sewing machine, in combination, stitch-forming mechanism,feeding mechanism for effecting the spacing of the stitches in the work,and work-shifting means acting' independently of the feeding mechanismand comprising a work-gripping device, a fixed fulcrum, means forturning said gripping device upon and for shifting itbodily transverselyof said fulcrum, and adjusting means constantly under the control of theoperator connected with said bodily shifting means and adapted to varythe extent of said bodily shifting movements.

1l. In a sewing machine, in combination, a work-gripping device, a fixedfulcrum, means for turning said gripping device upon and for shifting itbodily transversely of said fulcrum, adjusting means for determiningnormally the relative extent of said turning and bodily shiftingmovements, and additional shifting means constantly under the control ofthe opera-tor for temporarily varying such normal adjustment.

12. In a sewing machine, in combination, stitch-forming and feedingmechanisms, and worl -shifting means acting independently of saidfeeding mechanism and comprising a work-gripping device, a fulcrumtherefor, a reciprocating actuatingmember, and independent connectionsbetween said workgripping device and said actuating member for shiftingsaid gripping vdevice respectively about and transversely of saidfultransversely yof said fulcrum.

'crank-arm toward and from the rock-shaft.

15. In a sewing machine, in combination, a work-gripping devicecomprising opposed gripping elements Aand a carrier therefor,

lmeans for opening and closing said gripping device upon the worln'aparallel motion device comprising saidvcarrier as a member, andadjusting means for a member of' said parallel motion device for varyingthe extent of relative 'travelof different portions of said carrier.

16. In a sewing'machina in combination, a work-gripping device, shiftingmeans :for imparting thereto movements of a predetermined range, meansfor adju-sting vboth the extent and direction of said fmovements. andmeans constantly under the control of lthe operator for further varyingthe direction of movement of said gripping device.

17. In a sewing machine, infcombination, a work-gripping'devica'shifting means for imparting thereto movements of a predeterminedrange, means for adjusting both the extent and direction of saidmovements, and means constantly under the control of the operator forfurther varying both the extent and thedirectionof movement of saidgripping'device.

18. Ina sewing machine, in combination, feeding mechanism, aworlcgripping device, shifting means operable in alternation with thefeeding mechanism for imparting to the work-gripping ldevice 'movements`of a vpredetermined range, means for adjusting both the extent anddirection of said movements,

and means constantly under the control of the operator Vfor furthervarying either the extent or direction of movement of said grippingdevice.

19. In a sewing machine, in combination, stitchforming` mechanism, aworkgripping device, and shifting means operable intermediate `operativeperiodswo'f the stitchingforming mechanism for producing between themrelative travelling 'movements inapredetermined path, said shiftingmeans being provided with adjusting means whereby said path of relativetravel maybe lrectilinear or curvilinear in form.

'20. In a sewing machine, in combination,

stitch-forming mechanism, a work-gripping device, shifting means ;forproducing between them relative travelling movements 'in avpredetermined path, adjusting means forzthe shifting means whereby saidpath of relative .travel may be `rectilineario1- nirvilinear in form,`and means constantly under the control of the operator for furthervarying said path of relative travel.

21. In a buttonhole sewing machine, in combination, stitch-formingmechanism, a travelling work-cutting device comprising opposedwork-engaging elements, means for imparting to said cutting elements insuccessive stages nippingfollowed by cuttingmovements, and shiftingmeans connected with said cutting device and adapted to move the samewhile its cutting elements are in nipping relation in a curved pathtoward the stitch-forming mechanism, said shitting device being providedwith adjusting means whereby the degree of curvature of said path may bedetermined between a predetermined maximum of curvature and a straightline.

22.*ln a buttonhole sewing machine, in combination, stitch-formingmechanism, a travelling work-cutting device comprising opposedwork-engaging elements, means for imparting to said cutting elements insuccessive stages nippingfollowed by cuttingmovements, shifting meansconnected with said cutting device for movement thereof in a curved pathtoward the stitch-forming mechanism while its cutting elements are innipping relation, adjusting means for said shifting means whereby'thedegree of curvature of said path may be determined between apredetermined maximum of curvature and a straight line, and meansconstantly under the control of the operator for further varying thedegree of curvature of said path.

23. In a sewing machine, in combination, stitch-forming mechanism,feeding mechanism for imparting thereto travelling movements in adefined path during the sewing periods, and shifting means; acting uponthe work between sewing periods and adjustable to move it in pathsrespectively ot' different character in relation to the path of travelof the stitch-forming mechanism.

24. A buttonhole sewing machine, having, in combination, a rotary stitchforming mechanism and a work-clamp relatively movable to sew about abuttonhole, and means for moving the work in a variable curved path tospace the buttonholes.

25. A buttonhole sewing machine having, in combination, buttonholesewing mechanism, work spacing means, and adjusting means for varyingthe direction of the work spacing movements while the machine is inoperation.

In testimony whereof, I have signed my name to this specification.

ALBERT H. DE von.

